A statement that seems to contradict itself or common sense, but which, once thought through, reveals a truth.
In Purgatory
This mountain is such that it is always hard at the start, from below; and the more one climbs, the less it hurts. Therefore, when it seems so gentle to you that climbing will be light, like going downstream in a boat with the current.
The mountain is "hard" at the start, and "the more one climbs, the less it hurts." What common sense expects in reverse, that the summit be the harshest, is undone by the rule, which can only be understood by thinking about the will that grows stronger.
Cantos I to IV: The shore and Ante-Purgatory, Virgil, to Dante, answering how much is left to climb
that infinite and ineffable good that is up there runs to love as the ray comes to a shining body. It gives as much as it finds of ardor; so that, however much charity extends, the eternal worth grows over it.
Cantos XIII to XVI: Envy and wrath, Virgil, to Dante, explaining why divine good grows when shared
not only once, going around this space, is our pain refreshed: I say pain and should say consolation, because that will leads us to the trees, which led Christ joyfully to say Eli, when he freed us with his blood.
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